The U.S. Army's Signal Intelligence Service, the precursor to the National Security Agency, began a secret program in February 1943 later codenamed VENONA

The mission of this small program was to examine and exploit Soviet diplomatic communications but after the program began, the message traffic included espionage efforts as well.

Although it took almost two years before American cryptologists were able to break the KGB encryption, the information gained through these transactions provided U.S. leadership insight into Soviet intentions and treasonous activities of government employees until the program was canceled in 1980.

The VENONA files are most famous for exposing Julius (code named LIBERAL) and Ethel Rosenberg and help give indisputable evidence of their involvement with the Soviet spy ring.

The first of six public releases of translated VENONA messages was made in July 1995 and included 49 messages about the Soviets' efforts to gain information on the U.S. atomic bomb research and the Manhattan Project. Over the course of five more releases, all of the approximately 3,000 VENONA translations were made public.

 21SEP_BOMBING.PDFBritish bombing raids in Europe 21 September 1943 (Release 4)
 8NOV_BRITISH_FOREIGN_OFFICE_TELEGRAMS.PDFBritish foreign office telegrams supplied by CLAUDE 8 November (Release 5)
 2OCT_BRITISH_GOV_VIEWS.PDFBritish Government views; Breaking of a Soviet code reported bt INTELLIGENTSIA and the X Group; and German bombing
 17NOV_CHARLIE.PDFBritish Intelligence officer turned over by CHARLIE 17 November 1943 (Release 2)
 22JUN_SEC_COORDINATION.PDFBritish/U.S. security coordination 22 June 1943 (Release 2)
 28JAN_BROTHER_IN_LAWS.PDFBROTHER-IN LAW'S connection with the MILITARY NEIGHBOURS and with the Swedes
 4SEP_BROWNS_REPORT.PDFBrown's report to Slant on Asdic
 29OCT_BRYKIN_ARRIVES_LONDON.PDFBrykin reports his arrival in London; Strepetov 29 October (Release 5)
 25MAY_BUDGET_ALLOCATIO_MONTEVIDEO.PDFBudget allocation to Montevideo 25 May (Release 5)
 17MAR_BUDGET_DATA.PDFBudget data concerning the 5th line in NYC 17 March (Release 3)
 29APR_BUDGET_MATTERS.PDFBudget matters 29 April (Release 4)
 11JUL_BUDGET.PDFBudgetary and ship movements message 11 July 1943 (Release 4)
 1APR_BUDGET.PDFBudgetary matters 1 April 1943 (Release 4)
 24APR_BUDGET.PDFBudgetary matters 24 April 1943 (Release 4)
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